Question

1-cos theta /sin theta =sin theta / 1+cos theta

Answer 1

1-cos theta/sin theta = sin theta /1+ cost theta

cross multiplying

(1-cos theta )(1+cos theta)=(sin theta )(sin theta)

Here (a+b)(a-b)=a^2-b^2 is used

so,1^2-costheta^2=sin theta^2

1-costheta^2=sintheta^2

By identity 1

sin ^2=1-cos^2

Answer 2

Answer:

1-cos theta/sin theta = sin theta /1+ cost theta

cross multiplying

(1-cos theta )(1+cos theta)=(sin theta )(sin theta)

Here (a+b)(a-b)=a^2-b^2 is used

so,1^2-costheta^2=sin theta^2

1-costheta^2=sintheta^2

By identity 1

sin ^2=1-cos^2

Step-by-step explanation: